1. Field of the Invention:
The present invention relates to economizers for power-supply optimization, and more particular, to a dry type economizer, which eliminates the use of any insulating oil for heat dissipation, preventing component degradation.
2. Description of the Related Art:
An economizer is a mechanical device to be used for power-supply optimization during power conversion for energy efficiency. An economizer eliminates excess electricity by: absorbing reactive power through a reactance effect, restricting the access point over-voltage, removing noises and harmonic waves from the delivering power supply to eliminate unnecessary electromagnetic induction. Thus, an economizer can make full use of clean, high-load electricity, saving electricity costs and prolonging equipment lifespan.
In the reactance filter circuit structure of a conventional economizer, multi-stage switching devices are used for controlling different power factors. During operation of the reactance elements and switching devices, the electronic circuit will generate a large amount of heat, and therefore a cooling operation is necessary to lower the temperature.
Taiwan utility model patent M447475, issued to the present inventor, discloses an economizer entitled “Self-cooled economizer”. As illustrated in FIG. 1 and FIG. 2, this design of self-cooled economizer comprises a body 10, a plurality of guide tubes 11 located at two opposite lateral sides of the body 10 and arranged in two rows at different elevations, and multiple sets of radiation fins 12 arranged at each of the two opposite lateral sides of the body 10 between the two rows of guide tubes 11, an electrical insulating oil 13 enclosed in the body 10, an economizing unit 14 mounted in the body 10 and surrounded by the electrical insulating oil 13, and an input casing 15 and an output casing 16 respectively electrically connected to the economizing unit 14 and extended out of the top wall of the body 10. Further, the economizing unit 14 has built therein a plurality of reactance elements (not shown) electrically connected to respective filter converters (not shown) that are electrically connected to switch means. The electrical insulating oil 13 fills up the internal space of the body 10 and the guide tubes 11 to work with the multiple sets of radiation fins 12 for heat dissipation. The self-cooled economizer further comprises a switch unit 17 mounted in a control zone at an outside wall of the body 10, and other electrical insulating oil fitting components, such as drain valve 18 and oil level meter 19. Through the aforesaid structural arrangement, the self-cooled economizer achieves heat dissipation and power-supply optimization.
However, the use of the electrical insulating oil 13, drain valve 18 and oil level meter 19 greatly complicates the operation and control of the economizer. The internal electrical insulating oil 13 can absorb oxygen and moisture from the air to produce grease stain, increasing the water content and causing components degradation.